I have a P0401 code on, and have been reading all the good info on the site about dealing with this issue. My truck is a 1997 F150 4.2 Something that I found might be related is that my climate control vac is not working. After reading post on the site I was lead to a main vac junction behind my battery. Low and behold that junction has a few broken ports from the white plastic ports. After discovering this i went ahead and tested the egr with a hand held vac pump. I pulled vac on the egr while idiling and the engine almost stalled out, also the pressure gauge read steady (no vac bleed off) I need to replace that broken junction behind the battery and get the hoses drawing vac before I go on. My question is, has anybody ever replaced that vac junction? I can't seem to be able to find that part anywhere, even on the Ford Dealer sites. Is there somewhere that sells the junction and the hard plastic lines and connenctors besides the dealer?

 

Look in the help parts section of an auto parts store, they have different vacuum trees there.

 

I would just go to the dealership. They can pull up a parts blow-up and have you look right at what you need. Been there, done that.

But yeah, if your egr is working fine and you have vacuum leaks, then I would go that route first. P0401 is also common for the dpfe. You can also check the hoses from the egr pipe to the dpfe. I've seen those rot and clog. Napa sells a replacement set for about $6.